Electrochemical Reaction Cell

Abstract

To provide an electrochemical reaction cell capable of further uniformly supplying a liquid used for a reaction without reducing a reaction area.SOLUTION: An electrochemical reaction cell 100 comprises: a plurality of spacers 10 that defines an interval between an oxidation reaction electrode 102 and a reduction reaction electrode 104 that are arranged to face each other; support columns 12 that are provided across the spacers 10; and a plurality of current plates 114 that is supported by the support columns 12 so as to keep a distance from each other, and regulates a flow of an electrolytic solution 108 flowing between the oxidation reaction electrode 102 and the reduction reaction electrode 104.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an electrochemical reaction cell. [Background technology]

[0002] An electrochemical reaction cell has been disclosed in which an electrode for a reduction reaction and an electrode for an oxidation reaction are placed opposite each other at a distance within a container, and an electrolyte solution is passed between the electrode for the reduction reaction and the electrode for the oxidation reaction, thereby causing a chemical reaction of a substance (reaction substrate) contained in the electrolyte solution (Patent Document 1).

[0003] Also, a configuration has been disclosed in which an electrolyte is flowed from an inlet to an outlet between a reduction reaction electrode and an oxidation reaction electrode, and a fin is provided to restrict the flow of the electrolyte (Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-087074 [Patent Document 2] Japanese Patent Application Publication No. 2019-189929 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the configuration provided with fins in the prior art, the fins cover part of the reaction surfaces of the reduction reaction electrode and the oxidation reaction electrode, thereby reducing the area of ​​the region that can contribute to the reaction at each electrode. For example, in the configuration described in Patent Document 2, when the width of the flow path is 10 mm and the width of the fin is 6 mm, the area covered by the fins is 37.5% of the reaction area of ​​the reduction reaction electrode and the oxidation reaction electrode, which significantly reduces the reaction area and significantly reduces the reaction efficiency. [Means for solving the problem]

[0006] One aspect of the present invention is an electrochemical reaction cell comprising: a plurality of spacers that define a distance between an electrode for a reduction reaction and an electrode for an oxidation reaction that are arranged opposite to each other; supports that are provided between the spacers; and a plurality of rectifying plates that are supported by the supports so as to maintain a distance from each other and that regulate the flow of an electrolyte that flows between the electrode for a reduction reaction and the electrode for an oxidation reaction.

[0007] Here, it is preferable that the height of the rectifying plate along the stacking direction of the reduction reaction electrode and the oxidation reaction electrode is smaller than the height of the spacer, and that the reaction surfaces of the reduction reaction electrode and the oxidation reaction electrode are spaced apart from the rectifying plate.

[0008] It is also preferable that a separator be attached to the support to separate the reduction reaction electrode and the oxidation reaction electrode.

[0009] Furthermore, it is preferable that the area of ​​each of the reduction reaction electrode and the oxidation reaction electrode covered by the current plate is 10% or less, and it is more preferable that the area of ​​each of the reduction reaction electrode and the oxidation reaction electrode covered by the current plate is 5% or less.

[0010] It is also preferable that the support pillars have corrosion resistance and insulating properties against the electrolyte. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an electrochemical reaction cell that can more uniformly supply the liquid used in the reaction without reducing the reaction area. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a perspective view showing a configuration of an electrochemical reaction cell according to an embodiment of the present invention. [Figure 2] 1 is a cross-sectional view schematically illustrating a configuration of an electrochemical reaction cell according to an embodiment of the present invention. [Figure 3]1 is a cross-sectional view schematically illustrating a configuration of an electrochemical reaction cell according to an embodiment of the present invention. [Figure 4] 3 is a plan (surface) view seen from the Y direction showing the configuration of a current plate and a separator in the embodiment of the present invention. FIG. [Figure 5] 4 is a plan view (rear view) seen from the Y direction showing the configuration of a current plate and a separator in the embodiment of the present invention. FIG. [Figure 6] FIG. 2 is a cross-sectional view showing the configuration of a current plate and a separator according to the embodiment of the present invention. [Figure 7] FIG. 10 is a diagram showing the results of analyzing the flow of fluid in a configuration in which no flow straightening plate is provided. [Figure 8] 10A and 10B are diagrams illustrating the results of analyzing the flow of a fluid in an embodiment of the present invention. [Figure 9] FIG. 4 is a diagram showing the distribution of fluid flow velocity in an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] As shown in the perspective view of FIG. 1 and the cross-sectional views of FIGS. 2 and 3, the electrochemical reaction cell 100 according to the embodiment of the present invention includes an oxidation reaction electrode 102, a reduction reaction electrode 104, a separator 106, an electrolyte 108, a container 110, an orifice plate 112, and a rectifier plate 114.

[0014] Fig. 2 shows a cross-sectional view of the electrochemical reaction cell 100 cut along the YZ plane when the electrolytic solution 108 is not being supplied. Fig. 3 shows a cross-sectional view of the electrochemical reaction cell 100 cut along the YZ plane when the electrolytic solution 108 is being supplied.

[0015] The oxidation reaction electrode 102 and the reduction reaction electrode 104 are plate-shaped members extending in the X and Z directions, respectively, and are arranged to face each other along the Y direction. In this embodiment, the oxidation reaction electrode 102 and the reduction reaction electrode 104 are arranged with the separator 106 sandwiched between them so that their reaction surfaces extending in the XZ plane direction and carrying catalysts face each other.

[0016] 2 and 3, the electrode for oxidation reaction 102, the separator 106, and the electrode for reduction reaction 104 are arranged along the Y direction, then the electrode for reduction reaction 104, the separator 106, and the electrode for oxidation reaction 102 are arranged along the Y direction, then the electrode for oxidation reaction 102, the separator 106, and the electrode for reduction reaction 104 are arranged along the Y direction, then the electrode for reduction reaction 104, the separator 106, and the electrode for oxidation reaction 102 are arranged along the Y direction, and then the electrode for oxidation reaction 102, the separator 106, and the electrode for reduction reaction 104 are arranged along the Y direction. In other words, a plurality of electrode sets each consisting of the electrode for oxidation reaction 102, the separator 106, and the electrode for reduction reaction 104 are stacked along the Y direction.

[0017] The reduction reaction electrode 104 is an electrode used to reduce a substance through a reduction reaction. The reduction reaction electrode 104 has a structure in which a conductive layer and a reduction catalyst layer are laminated on a substrate. The substrate is a member that structurally supports the reduction reaction electrode 104 and may include, for example, an insulator such as a glass substrate, a metal including titanium (Ti), silver (Ag), gold (Au), or a semiconductor including titanium oxide (TiO), tin oxide (SnO), silicon (Si), or the like. When the substrate is an insulator, a conductive layer is provided between the substrate and the reduction catalyst layer. The conductive layer is provided to apply a voltage to the reduction catalyst layer of the reduction reaction electrode 104. The conductive layer is not particularly limited, but is preferably a transparent conductive layer such as indium tin oxide (ITO), fluorine-doped tin oxide (FTO), or zinc oxide (ZnO). The reduction catalyst layer is composed of a material with reduction catalytic function. The reduction catalyst layer preferably contains a complex catalyst. The reduction catalyst layer is preferably a ruthenium complex, such as [Ru{4,4'-di(1-H-1-pyrrolypropyl carbonate)-2,2'-bipyridine}(CO)(MeCN)Cl2], [Ru{4,4'-di(1-H-1-pyrrolypropyl carbonate)-2,2'-bipyridine}(CO)2Cl2], or [Ru{4,4'-di(1-H-1-pyrrolypropyl carbonate)-2,2'-bipyridine}(CO)2]. n , [Ru{4,4'-di(1-H-1-pyrrolypropyl carbonate)-2,2'-bipyridine}(CO)(CHCN)Cl], etc.

[0018] Modification with a complex catalyst can be achieved by dissolving the complex in acetonitrile (MeCN) solution and applying it to the conductive layer. Modification with a complex catalyst can also be achieved by electrolytic polymerization. The working electrode is the conductive layer, the counter electrode is a glass substrate coated with fluorine-containing tin oxide (FTO), and the reference electrode is Ag / Ag. + Using an electrode, Ag / Ag in an electrolyte containing a complex catalyst +After applying a cathodic current to the electrode to create a negative voltage, Ag / Ag + By passing an anodic current so that the electrode is at a positive potential, the surface of the conductive layer can be modified with a complex catalyst. The electrolyte solution can be acetonitrile (MeCN), and the electrolyte can be tetrabutylammonium perchlorate (TBAP).

[0019] The reduction catalyst layer can also be made of a material containing a carbon material (C). The size of the single unit of the carbon material structure is preferably 1 nm or more and 1 μm or less. The carbon material preferably contains at least one of carbon nanotubes, graphene, and graphite, for example. In the case of graphene and graphite, the size is preferably 1 nm or more and 1 μm or less. In the case of carbon nanotubes, the diameter is preferably 1 nm or more and 40 nm or less. The conductor can be formed by spraying a carbon material mixed with a liquid such as ethanol, followed by heating. Spin coating may be used instead of spraying. Alternatively, the solution may be directly dripped and dried to apply the solution without using spin coating.

[0020] The oxidation reaction electrode 102 is an electrode used to oxidize a substance through an oxidation reaction. The oxidation reaction electrode 102 is formed on a substrate. The oxidation reaction electrode 102 is composed of a conductive layer and an oxidation catalyst layer. The substrate is a member that structurally supports the oxidation reaction electrode 102 and can be made of, for example, the same material as the substrate used for the reduction reaction electrode 104. When the substrate is an insulator, a conductive layer is provided between the substrate and the oxidation catalyst layer. The conductive layer is provided to apply a voltage to the oxidation catalyst layer of the oxidation reaction electrode 102. The conductive layer is preferably made of indium tin oxide (ITO), fluorine-doped tin oxide (FTO), zinc oxide (ZnO), or the like. The oxidation catalyst layer is composed of a material having an oxidation catalyst function. The material having an oxidation catalyst function can be, for example, a material containing iridium oxide (IrOx).

[0021] Iridium oxide can be supported on the surface of a conductive layer as a nanocolloid solution. For example, nanocolloids of iridium oxide (IrOx) are synthesized. Next, 50 ml of 2 mM potassium chloroiridate(IV) (K2IrCl6) aqueous solution is added with 10 wt% sodium hydroxide (NaOH) aqueous solution to adjust the pH to 13. The resulting yellow solution is heated at 90°C for 20 minutes using a hot stirrer. The resulting blue solution is cooled in ice water for 1 hour. 3 M nitric acid (HNO3) is then added dropwise to the cooled solution (20 ml) to adjust the pH to 1. The solution is then stirred for 80 minutes to obtain a nanocolloid solution of iridium oxide (IrOx). This solution is then adjusted to pH 12 by adding 1-2 ml of 1.5 wt% NaOH aqueous solution dropwise. The nanocolloidal aqueous solution of iridium oxide (IrOx) obtained in this manner is applied to the conductive layer at a pH of 12 and dried in a drying oven at 60°C for 40 minutes. After drying, the precipitated salt is washed with ultrapure water to form the oxidation reaction electrode 102. The application and drying of the nanocolloidal aqueous solution of iridium oxide (IrOx) may be repeated multiple times.

[0022] The electrochemical reaction cell 100 can also be configured such that adjacent pairs of the oxidation reaction electrodes 102 are bonded together at their backsides along the stacking direction (Y direction) and the reduction reaction electrodes 104 are bonded together at their backsides, so that the oxidation reaction electrodes 102, the reduction reaction electrodes 104, the reduction reaction electrodes 104, the oxidation reaction electrodes 102, ... are stacked and housed in a single container 110. Alternatively, adjacent pairs of the oxidation reaction electrodes 102 can be configured such that oxidation catalyst layers are formed on both sides of the substrate of the reduction reaction electrode 104, and reduction catalyst layers are formed on both sides of the substrate of the reduction reaction electrode 104, so that the oxidation reaction electrodes 102, the reduction reaction electrodes 104, the reduction reaction electrodes 104, the oxidation reaction electrodes 102, ... are stacked and housed in a single container 110.

[0023] The electrochemical reaction cell 100 functions by introducing an electrolyte 108 between the reduction reaction electrode 104 and the oxidation reaction electrode 102. That is, as shown in Fig. 3, a container 110 is placed so as to surround the reduction reaction electrode 104 and the oxidation reaction electrode 102, and the electrolyte 108, in which a reactant is dissolved, is supplied to the surfaces of the reduction reaction electrode 104 and the oxidation reaction electrode 102.

[0024] The reactant may be a carbon compound, such as carbon dioxide (CO2). The electrolyte 108 is preferably a phosphate buffer solution or a borate buffer solution. In a specific configuration example, a tank of carbon dioxide (CO2)-saturated phosphate buffer solution is provided, and the solution is supplied by a pump from an electrolyte supply port to the surfaces of the reduction reaction electrode 104 and the oxidation reaction electrode 102. Liquid products such as formic acid (HCOOH) produced by the reduction reaction are discharged together with the electrolyte 108 from the electrolyte outlet 110b, and are collected in an external fuel tank. Gas products such as carbon monoxide (CO) produced by the reduction reaction are discharged from the gas outlet 110c, and are collected in an external fuel tank.

[0025] In this embodiment, the oxidation reaction electrode 102 and the reduction reaction electrode 104 are arranged in the container 110 so that the reaction surface on which the catalyst is supported is in the vertical direction (XZ plane direction). In addition, in this embodiment, a configuration is adopted in which a plurality of sets 120 of the oxidation reaction electrode 102 and the reduction reaction electrode 104 are stacked along the Y direction.

[0026] It is also preferable to electrically connect the reduction reaction electrode 104 and the oxidation reaction electrode 102 and apply an appropriate bias voltage thereto. The means for applying the bias voltage is not particularly limited, and examples thereof include a chemical battery (including a primary battery, a secondary battery, etc.), a constant voltage source, a solar cell, etc. In this case, the positive electrode is connected to the oxidation reaction electrode 102, and the negative electrode is connected to the reduction reaction electrode 104. The connection between the oxidation reaction electrode 102 and the reduction reaction electrode 104 may be set appropriately. For example, some of the oxidation reaction electrodes 102 and the reduction reaction electrodes 104 may be connected in series, parallel, or series-parallel. Furthermore, a switch for switching the connection may be provided to change the connection configuration of the oxidation reaction electrode 102 and the reduction reaction electrode 104 to the bias power supply.

[0027] When a solar cell is used as the bias power supply, the solar cell can be arranged adjacent to the oxidation reaction electrode 102 and the reduction reaction electrode 104. For example, a solar cell can be arranged on the backside of the reduction reaction electrode 104, with the positive electrode of the solar cell connected to the oxidation reaction electrode 102 and the negative electrode connected to the reduction reaction electrode 104. When a solar cell is used as the bias power supply, if a set of the oxidation reaction electrode 102 and the reduction reaction electrode 104 is used alone, the solar cell may be used at an operating point where its efficiency is poor. On the other hand, if multiple sets of the oxidation reaction electrode 102 and the reduction reaction electrode 104 are connected in parallel, it becomes possible to use the solar cell at an operating point where its efficiency is good.

[0028] When synthesizing formic acid (HCOOH) from carbon dioxide (CO2), water (H2O) is oxidized to provide electrons and protons to carbon dioxide (CO2). At a pH of around 7, the oxidation potential of water (H2O) is 0.82 V, and the reduction potential is -0.41 V (both NHE). Furthermore, the reduction potentials of carbon dioxide (CO2) to carbon monoxide (CO), formic acid (HCOOH), and methyl alcohol (CH3OH) are -0.53 V, -0.61 V, and -0.38 V, respectively. Therefore, the potential difference between the oxidation potential and reduction potential is 1.20 to 1.43 V.

[0029] The container 110 is a member that supports the oxidation reaction electrode 102, the reduction reaction electrode 104, the separator 106, the rectifying plate 114, etc., and also forms a flow path through which the electrolyte 108 flows. The container 110 is made of a material that has the mechanical strength necessary to form the electrochemical reaction cell 100 as a cell. For example, the container 110 can be made of metal, plastic, etc.

[0030] The container 110 is provided with an electrolyte solution supply port 110a for supplying the electrolyte solution 108 into the container 110. The container 110 is also provided with an electrolyte solution discharge port 110b for discharging the electrolyte solution 108 from the container 110. That is, the electrolyte solution 108 containing the substance to be reacted is supplied into the container 110 from the electrolyte solution supply port 110a, and the electrolyte solution 108 is caused to flow through the reaction region between the oxidation reaction electrode 102 and the reduction reaction electrode 104, and then the electrolyte solution 108 is discharged to the outside of the container 110 from the electrolyte solution discharge port 110b.

[0031] The container 110 is also provided with a gas exhaust port 110c for discharging gas generated by the reaction in the electrochemical reaction cell 100 from the container 110. It is preferable to arrange the gas exhaust port 110c in the container 110 vertically above the reaction region in which the oxidation reaction electrode 102 and the reduction reaction electrode 104 are arranged.

[0032] The electrochemical reaction cell 100 is further provided with an orifice plate 112. The orifice plate 112 is a member provided with orifice holes 112a and 112b, which are through-holes that restrict the flow of the electrolyte 108 introduced into the container 110 from the electrolyte supply port 110a. The orifice plate 112 is disposed in a flow path in the container 110 that extends from the electrolyte supply port 110a to the region where the oxidation reaction electrode 102 and the reduction reaction electrode 104 are provided. The orifice plate 112 is made of a material that has the necessary mechanical strength. For example, the orifice plate 112 can be made of metal, plastic, or the like.

[0033] 4 to 6 show the configurations of the rectifier plate 114 and separator 106 used in the electrochemical reaction cell 100. Fig. 4 and Fig. 5 show the configurations of the front and back surfaces of the oxidation reaction electrode 102 and the reduction reaction electrode 104 in the electrochemical reaction cell 100 as viewed from the stacking direction (Y direction). Fig. 6 is an enlarged view as viewed from the flow direction (Z direction) of the electrolytic solution 108.

[0034] The current plate 114 is mechanically supported by a frame formed by combining the spacers 10 and the support posts 12 .

[0035] The spacers 10 are rod-shaped members arranged along the flow direction (Z direction) of the electrolyte 108. The material of the spacers 10 is not particularly limited, but is preferably an electrically insulating material that is resistant to corrosion and damage by the electrolyte 108. The spacers 10 are arranged on both sides of the frame. The spacers 10 are used as members that mechanically support the current plate 114 and the separator 106, and can also be used as members that define the gap between the oxidation reaction electrode 102 and the reduction reaction electrode 104 that are arranged opposite each other. For example, if the gap between the oxidation reaction electrode 102 and the reduction reaction electrode 104 is desired to be 10 mm, the height h1 of the spacers 10 is preferably 10 mm. The width t1 of the spacers 10 is preferably 10 mm, for example.

[0036] The support pillars 12 are members that constitute the frame together with the spacers 10. The support pillars 12 are arranged in a direction intersecting the flow direction (Z direction) of the electrolyte 108, and connect the spacers 10 arranged on both sides of the frame. The support pillars 12 can maintain a constant spacing between the spacers 10. In addition, the rectifying plates 114 are fixed to the support pillars 12. Therefore, the support pillars 12 can maintain a constant spacing between the rectifying plates 114. The number of support pillars 12 is not particularly limited, but it is preferable to use a number that can maintain the spacing between the spacers 10 and the rectifying plates 114 as uniform as possible.

[0037] The material forming the support 12 is preferably an electrically insulating material that is resistant to corrosion and damage caused by the electrolyte 108. For example, the support 12 is preferably formed by covering a metal rod with a heat-shrinkable tube made of resin.

[0038] The rectifying plate 114 is a member that restricts the flow of the electrolyte 108 in the electrochemical reaction cell 100. The material that constitutes the rectifying plate 114 is not particularly limited, but it is preferable that the rectifying plate 114 be made of a material that is resistant to corrosion and damage by the electrolyte 108 and has electrical insulation properties. The rectifying plate 114 is a plate-shaped member that extends along the direction in which the electrolyte 108 flows (Z direction).

[0039] The height of the rectifying plate 114 in the stacking direction (Y direction) of the oxidation reaction electrode 102 and the reduction reaction electrode 104 and the width in the in-plane direction (X direction) of the oxidation reaction electrode 102 and the reduction reaction electrode 104 may be set appropriately. However, the height h2 of the rectifying plate 114 in the stacking direction (Y direction) of the oxidation reaction electrode 102 and the reduction reaction electrode 104 is set to be equal to or less than the height h1 of the spacer 10, and more preferably less than the height h1. For example, if the height h1 of the spacer 10 is set to 10 mm, the height h2 of the rectifying plate 114 is preferably set to 8 mm.

[0040] By making the height h2 of the rectifying plate 114 less than the height h1 of the spacer 10, in a state in which the spacer 10 is sandwiched between the oxidation reaction electrode 102 and the reduction reaction electrode 104 to set the gap between the oxidation reaction electrode 102 and the reduction reaction electrode 104 to the height h1, it is possible to provide a gap between the rectifying plate 114 and the surfaces of the oxidation reaction electrode 102 and the reduction reaction electrode 104. As a result, as will be described later, the flow of the electrolyte 108 can be made uniform by the rectifying plate 114, and no area on the surfaces of the oxidation reaction electrode 102 and the reduction reaction electrode 104 is covered by the rectifying plate 114, and the utilization efficiency of the oxidation reaction electrode 102 and the reduction reaction electrode 104 can be improved.

[0041] Furthermore, in the electrochemical reaction cell 100, the spacers 10 and the support columns 12 form a frame supporting the rectifying plates 114. The support columns 12 maintain uniform spacing between the rectifying plates 114, allowing the width t2 of the rectifying plates 114 to be small. For example, the width t2 of the rectifying plates 114 in the X direction can be 2 mm. When 18 rectifying plates 114 with a width t2 of 2 mm are arranged on a 1 m square oxidation reaction electrode 102 and a reduction reaction electrode 104, the area covered by the rectifying plates 114 relative to the reaction area of ​​the oxidation reaction electrode 102 and the reduction reaction electrode 104 can be reduced to 4.0%. This increases the reaction area compared to conventional configurations, thereby improving the reaction efficiency of the electrochemical reaction cell 100. In this way, the area covered by the rectifying plates 114 in the electrochemical reaction cell 100 can be reduced to 10% or less, and even to 5% or less.

[0042] The separator 106 is a member that separates the oxidation reaction electrode 102 and the reduction reaction electrode 104. The separator 106 can be made of a proton-conducting film, which is a porous body that can transmit protons in the electrolyte 108. The separator 106 can be made of, for example, at least one of a rayon nonwoven fabric, a vinylon nonwoven fabric, a hydrophilized ultra-high molecular weight polyethylene porous film, a hydrophilized polypropylene mesh, and a hydrophilized ultra-high molecular weight polyethylene porous film. Note that if the separator 106 is not required, the separator 106 may not be provided.

[0043] In the electrochemical reaction cell 100, rectangular flat separators 106 can be arranged in each region partitioned by a current plate 114 extending along the flow direction (Z direction) of the electrolyte 108, facing the surfaces of the oxidation reaction electrode 102 and the reduction reaction electrode 104. Each separator 106 may be fixed by, for example, attaching it to a support 12.

[0044] 7 and 8 show the results of fluid analysis of the flow of the electrolyte 108 when the height h1 of the spacer 10 was set to 10 mm, the oxidation reaction electrode 102 and the reduction reaction electrode 104 were spaced 10 mm apart and arranged facing each other in the Y direction, and the electrolyte 108 was caused to flow from bottom to top in the Z direction. FIG. 7 shows the results of fluid analysis for a configuration in which the rectifying plate 114 was not provided. FIG. 8 shows the results of fluid analysis for a configuration in which the rectifying plate 114 was extended and arranged along the Z direction, and the height h2 of the rectifying plate 114 was set to 8 mm. In both cases, the flow was analyzed when a fluid (water) was flowing at 32 L / min.

[0045] As shown in Fig. 7, in the configuration without the current rectifier 114, turbulence occurred in the direction of the flow in the lower part of the flow path. Also, there were areas where the flow velocity of the fluid was significantly reduced. On the other hand, as shown in Fig. 8, in the configuration with the current rectifier 114, the fluid flowed along the current rectifier 114, and the flow was regulated from the bottom to the top of the flow path.

[0046] 9 shows the results of determining the flow velocity at 10 evaluation points on a line (line A in FIGS. 7 and 8) that cuts the flow path from the bottom to the top in the X direction. In the configuration without the flow straightening plate 114, the standard deviation of the flow velocity is 9.35×10 -4 However, in the configuration with the current plate 114, the standard deviation of the flow velocity was 7.00 × 10 -4 In this way, in the configuration provided with the current plate 114, the distribution of the fluid flow velocity in the X direction was more uniform than in the configuration without the current plate 114. [Explanation of symbols]

[0047] 10 spacer, 12 support, 100 electrochemical reaction cell, 102 electrode for oxidation reaction, 104 electrode for reduction reaction, 106 separator, 108 electrolyte, 110 container, 110a electrolyte supply port, 110b electrolyte outlet, 110c gas exhaust port, 112 (112a, 112b) orifice plate, 114 rectifier plate.

Claims

1. a plurality of spacers that are sandwiched between a plate-shaped reduction reaction electrode and a plate-shaped oxidation reaction electrode that are disposed opposite to each other and that define a distance between the reduction reaction electrode and the oxidation reaction electrode; a support pillar provided between the spacers; a plurality of rectifying plates supported by the support pillars at intervals from one another and regulating the flow of the electrolyte flowing between the reduction reaction electrode and the oxidation reaction electrode; Equipped with an electrochemical reaction cell, characterized in that the rectifying plate extends along a direction from a supply side to a discharge side of the electrolytic solution in a flow path of the electrolytic solution between the reduction reaction electrode and the oxidation reaction electrode, and is not provided along a direction intersecting the direction.

2. 2. The electrochemical reaction cell according to claim 1, an electrochemical reaction cell characterized in that the height of the current plate along the stacking direction of the reduction reaction electrode and the oxidation reaction electrode is smaller than the height of the spacer, and the current plate is spaced apart from the reaction surfaces of the reduction reaction electrode and the oxidation reaction electrode over the entirety of the current plate.

3. 3. The electrochemical reaction cell according to claim 1 or 2, An electrochemical reaction cell, characterized in that a separator is attached to the support to separate the reduction reaction electrode and the oxidation reaction electrode.

4. An electrochemical reaction cell according to claim 1, an electrochemical reaction cell, characterized in that the thickness of the support pillar along the stacking direction of the reduction reaction electrode and the oxidation reaction electrode is smaller than the thickness of the current plate along the stacking direction.

5. 2. The electrochemical reaction cell according to claim 1, An electrochemical reaction cell, characterized in that the area of ​​each of the reduction reaction electrode and the oxidation reaction electrode covered by the current plate is 10% or less.

6. 6. The electrochemical reaction cell according to claim 5, An electrochemical reaction cell, characterized in that the area of ​​each of the reduction reaction electrode and the oxidation reaction electrode covered by the current plate is 5% or less.

7. The electrochemical reaction cell according to any one of claims 1 to 6, The electrochemical reaction cell is characterized in that the support pillars are corrosion-resistant and insulating against the electrolyte.

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